Ultraviolet spectra of planetary nebulae - V. The C II 1335 dielectronic recombination lines in IC 418
نویسندگان
چکیده
منابع مشابه
Emission lines of O III in the optical and ultraviolet spectra of planetary nebulae
Recent R-matrix calculations of electron impact excitation rates in O iii are used to calculate electron temperature and density-dependent emission line ratios R1 = I(4363 Å)/I(4960 Å + 5007 Å), R2 = I(1661 Å + 1667 Å)/I(4960 Å + 5007 Å) and R3 = I(2322 Å)/I(1661 Å + 1667 Å), for a range of electron temperatures (7500 ≤ Te ≤ 30 000 K) and densities (104 ≤ Ne ≤ 107 cm−3) applicable to gaseous ne...
متن کاملOptical recombination lines as probes of conditions in planetary nebulae
Since the last IAU symposium on planetary nebulae (PNe), several deep spectroscopic surveys of the relatively faint optical recombination lines (ORLs) emitted by heavy element ions in PNe and H ii regions have been completed. New diagnostic tools have been developed thanks to progress in the calculations of basic atomic data. Together, they have led to a better understanding of the physical con...
متن کاملThe O Ii Recombination Line Abundance Problem in Planetary Nebulae
Presentamos observaciones de ĺıneas de recombinación de O II en diez nebulosas planetarias brillantes, y mediciones de O II y [O III] con resolución espacial en NGC 6720. Esto es con el fin de estudiar la discrepancia entre las abundancias calculadas con ĺıneas de recombinación de O II y aquellas derivadas de ĺıneas de excitación colisional de [O III]. Observamos una gran variación en la discre...
متن کاملExpansion Parallax of the Planetary Nebula Ic 418
In this paper, we present radio continuum observations of the planetary nebula IC 418 obtained at two epochs separated by more than 20 years. These data allow us to show that the angular expansion rate of the ionization front in IC 418 is 5.8 ± 1.5 mas yr−1. If the expansion velocity of the ionization front is equal to the expansion velocity of the gas along the line of sight as measured by opt...
متن کاملEmission Lines from Jets in Planetary Nebulae
Emission line profiles from collimated high-velocity outflows or jets in planetary nebulae (PNe) have diverse characteristics that indicate the influence of binary cores and magnetic confinement mechanisms in their origin. In this contribution, a number of cases are presented that exemplify the complexity of these outflows in PNe.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1981
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/197.2.301